package java01;

public class DataType_Study {

	public static void main(String[] args) {
for (int i=3;i>0 ; i--){
	System.out.print("A");
	for(int j=1 ;j<2 ; j++){
		System.out.print("B");
		for(int k=1 ;k<2 ; k++){
			System.out.print("C");
		}
	}
		
	System.out.print("D");
	}

	}
}